1. Field of the Invention
This invention relates to a template for mounting in a film cassette having structure to anchor the template in place. Indicia printed on the template and an image of a subject are to be simultaneously recorded on a film unit during its exposure which allows a size comparison of the same subject photographed at different times from the same location.
2. Description of the Prior Art
Techniques for measuring physical change in structures, shore lines, facial wounds, skin eruptions and the like may be documented by photographs of the subject. Two or more photographs of the same subject, taken at different times, allow a comparison of the feature of concern. To have comparable photographs requires that the camera be set in the same spacial location with respect to the subject. Thereby, the physical characteristic being photographed can be measured in each photograph to allow the comparison.
U.S. Pat. No. 2,322,032 to Kunze describes such a photographic technique to measure the progress of healing or changes in physical structure of the facial features of a patient.
A patent to Zimberoff, U.S. Pat. No. 3,102,459, uses the technique for identification of individuals by ear configuration and using a grid technique of concentric dots as an overlay to the photograph.
A patent to Chabot et al., U.S. Pat. No. 3,699,856, discloses photographing facial features with an overlay having a grid system which is superimposed on the photograph to allow the comparison of physical features of the same individual at separate times.
A patent to Ueda et al., U.S. Pat. No. 3,916,423, discloses a template having a grid system used in relation to photographs to measure physical sizes. The structure disclosed for retaining the template or overlay within the film cassette comprises transversely projecting ears from each side of the template to fit within the film cassette at the exposure opening.
A patent to Wheeler, U.S. Pat. No. 4,717,930, discloses a camera using instant photography techniques which incorporates a transparent template mounted in the exposure opening of a film cassette inserted into the camera.
Placing templates in the exposure opening of a film cassette of instant photography-type cameras for purposes of having a particular indicia on each successive film frame is known as shown in the above cited patents. Other examples are disclosed in commonly owned, U.S. Pat. Nos. 5,142,311 and 5,144,348. All of those patents disclose techniques for trying to maintain the template properly anchored within the exposure opening of the film cassette from one photograph to another such that the resulting photographs are uniform with respect to the location of the indicia on the resulting photograph. Uniformity of location in the film frame is both the desire and the problem.
Frictional engagement between a template located within a film cassette and in direct contact with an adjacent film unit inherently results in a frictional engagement which may dislocate the template when the exposed underlying film unit (or dark slide) is ejected from the cassette in a normal instant film exposure and processing cycle. There is a need for a secure anchor for the template within the exposure opening, and indeed, the need for a secure anchor is acute where the template has a grid system for printing on the photograph in order to allow physical comparisons of photographs of the same subject taken at different times from the same location.